Re: [PATCH net] ice: fix setting promisc mode while adding VID filter

[Simon Horman <horms@kernel.org>]

On Fri, Mar 27, 2026 at 08:23:28AM +0100, Aleksandr Loktionov wrote:
> From: Marcin Szycik <marcin.szycik@intel.com>
> 
> There are at least two paths through which VSI promiscuous mode can be
> independently configured via ice_fltr_set_vsi_promisc():
> - ice_vlan_rx_add_vid() (netdev op)
> - ice_service_task() -> ... -> ice_set_promisc()
> 
> Both paths may try to program promiscuous mode concurrently. One such
> scenario is:
> 
> 1. Add ice netdev to bond
> 2. Add the bond netdev to bridge
> 3. ice netdev enters allmulticast mode (IFF_ALLMULTI)
> 4. Service task programs promisc mode filter
> 5. Bridge -> bond calls ice_vlan_rx_add_vid()
> 
> Crucially, ice_vlan_rx_add_vid() fails if ice_fltr_set_vsi_promisc()
> returns any error, including -EEXIST. This causes VLAN filtering setup
> to fail on the bond interface. ice_set_promisc() already handles -EEXIST
> correctly.
> 
> Fix by adding the same -EEXIST check to ice_vlan_rx_add_vid(): if the
> promisc filter is already programmed, continue without returning error.
> 
> Fixes: 1273f89578f2 ("ice: Fix broken IFF_ALLMULTI handling")
> Cc: stable@vger.kernel.org
> Signed-off-by: Marcin Szycik <marcin.szycik@intel.com>
> Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>

Reviewed-by: Simon Horman <horms@kernel.org>